When I first started getting into watches I would always see the comment " you can't compare the two" and it would always drive me up the wall. But after owning a GS, and now owning a Rolex I have to say that the finish on the GS is objectively better than Rolex (I have the YM 40 in blue). That said, I really do believe they approach watches and watchmaking in such a fundamentally different way that comparing them can be difficult.
I will say that I am absolutely in love with their new movement and can't wait to see it in more watches.